Yes, I have worn diapers while playing video games. IMHO, this is like asking if a caffeine addict has ever had a soda while doing any normal activity. As for good experiences, most will only be able to say that the diaper only delayed the inevitable. My experience is basically just that, rest room breaks were delayed until a more convenient time.
My most memorable time wearing diapers while playing video games was right after knee surgery. For the first two weeks of recovery, I was unable to walk far or drive. The recommended dosage of Percocet was 2 every 4 hours. Between the pain of walking, the difficulty of the stairs to get to my bathroom, and the side effects of the pain medication, I ended up spending too much time diapered in front of the computer. After a week and a half, I was so burned out on computer games that I did not play WoW for over a month. Several days were spent just sitting on my porch in a chair enjoying the weather.